Accelerators and Detectors - Nuclear and Particle Physics - Physics Previous Year Questions

A neutron passing through a detector is detected because of

An alpha particle is accelerated in a cyclotron. It leaves the cyclotron with a kinetic energy of 16 MeV. The potential difference between the D electrodes is 50 kilovolts. The number of revolutions the alpha particle makes in its spiral path before it leaves the cyclotron is _______.

Cyclotrons are used to accelerate ions like deuterons ($d$) and $\alpha$ particles. Keeping the magnetic field same for both, $d$ and $\alpha$ are extracted with energies 10 MeV and 20 MeV with extraction radii $r_d$ and $r_{\alpha}$, respectively. Taking the masses $M_d = 2000$ MeV/c$^2$ and $M_{\alpha} = 4000$ MeV/c$^2$, the value of $\frac{r_{\alpha}}{r_d}$ (in integer) is ____

The Geiger-Muller counter is a device to detect $\alpha$, $\beta$ and $\gamma$ radiations. It is a cylindrical tube filled with monatomic gases like argon, and polyatomic gases such as ethyl alcohol. The inner electrode is along the axis of the cylindrical tube and the outer electrode is the tube. Which of the following statements is(are) CORRECT?